Hereditary pyropoikilocytosis (HPP) is a severe, congenital hemolytic anemia occurring almost exclusively in black persons and characterized by extreme red blood cell anisopoikilocytosis. The authors report two unrelated white females with HPP. Both had severe hemolytic anemia at birth, red blood cell morphologic features characteristic for HPP, and increased thermal sensitivity of the red blood cells. Examination of the red blood cell membranes of both patients showed markedly unstable membrane skeletons when subjected to shear stress, spectrin dimer association defects with increased dimers, and partial spectrin deficiency. Limited tryptic digestion of the spectrin molecule from both patients yielded an abnormal pattern with a decrease in the normal 80,000-dalton αI domain and a concomitant increase of an abnormal 74,000-dalton peptide (Spα(1/74)). One parent and one sibling of one of the patients with HPP had hereditary elliptocytosis (HE) and the Spα(1/74) defect. The other patient with HPP was different from others reported in that both parents were hematologically and biochemically normal. In addition, her daughter had HE and the Spα(1/74) defect.
ASJC Scopus subject areas
- Pathology and Forensic Medicine